Cell Phones EC:

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10 Δεκ 2013 (πριν από 3 χρόνια και 6 μήνες)

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Cell Phones EC:


1)

What was life like before cell phones?

2)

What cell phone functions are important for you?

3)

Are there any features on your cell phone you don’t need?

4)

Can people use their cell phones while they are driving in your country?

5)

W
hat does the ‘cellular’ mean in cellular phone?

6)

Do you think cell phones are liberating?

7)

Would it be a big problem for you if your cell phone was lost or stolen?

8)

How often do you turn your cell phone off?

9)

Which cell phone maker is best?

10
)

Do you think cell phones really interfere with equipment in hospitals and on airplanes?

1
1)

What are the best things about cell phones?

1
2)

Do you get annoyed with other cell phone users?

1
3)

What do you do when you annoy other people with your cell p
hone?

1
4)

Do you think people should be fined for using their cell phone in a no cell phone area?

1
5)

Are you worried about brain damage from using cell phones?

1
6)

How do you feel if you leave the house without your cell phone?

1
7)

Do you think the ca
ll and rental charges for cell phones are reasonable?

1
8)

Have you ever slept with your cell phone?

1
9)

Do you have any complaints about cell phone batteries?

20)

Did you hear that using a cell phone near a gasoline stand can cause an explosion?

A
mobi
le phone

allows calls into the public switched telephone system over a radio link. Early mobile phones were usually bulky and
permanently installed in vehicles; they provided limited service because only a few frequencies were available for a geograph
ic ar
ea.
Modern
cellular "cell" phones

or
hand phones

make use of the
cellular network

concept, where frequencies are re
-
used repeatedly
within a city area, allowing many more u
sers to share access to the radio bandwidth. A mobile phone allows calls to be placed over a
wide geographic area; generally the user is a subscriber to the phone service and does not own the
base station
. By contrast, a
cordless
telephone

is used only within the range of a single, private base station.

A mobile phone can make and receive telepho
ne calls to and
from the
public telephone network

which includes other mobiles and
fixed
-
line

phones across the world. It do
es this by connecting to
a cellular network provided by a
mobile network operator
.

In addition to telephony, modern mobile phones also support a wide variety
of other
services

such as
text messaging
,
MMS

(multimedia messaging service)
, email, Internet access, short
-
range wireless
communications (
infrared
,
Bluetooth
), business applications, gaming and photography. Mobile phones that offer these more general
computing capabilities are referred to as
smartphones
.

The first hand
-
held mobile phone was demonstrated by
Dr Martin Cooper

of
Motorola

in 1973, using a handset weighing 2 1/2 lbs (about 1 kg).

In 1983, the
DynaTAC 8000x

was the first to be commercially
available. In the twenty years from 1990 to 2010, worldwide mobile phone subscriptions grew from 12.4 million to over 4.6 bil
lion,
penetrating the
developing economies

and reaching the
bottom of the ec
onomic pyramid
.

History
Radiophones

have a long and varied history going back to
Reginald Fessenden
's invention and shore
-
t
o
-
ship demonstration of radio telephony, through the
Second World War

with military use of radio telephony
links and civil services in the 1950s.

The first mobile telephone

call made from a car occurred in
St.
Louis, Missouri
, USA on June 17, 1946, using the
Bell S
ystem
's
Mobile Telephone Service
. The equipment
weighed 80 pounds (36

kg), and the
AT&T

servi
ce, basically a massive party line, cost US$30 per month
(equal to $337.33 today) plus 30

40 cents per local call, equal to $3.37 to $4.5 today.

In 1956, the
world’s first partly
aut
omatic

car phone system, Mobile System A (MTA), was launched in Sweden. MTA phones
were composed of
vacuum tubes

and
rela
ys
, and had a weight of 40

kg. In 1962, a more modern version called
Mobile System B (MTB)

was launched, which was a
push
-
button telephone
, and which used
transistors

to enhance
the telephone’s calling capacity and improve its operational reliability, thereby reducing the weight of
the apparatus to 10

kg. In 1971, the
MTD

version was launched, opening for several different brands of
equipment and gaining commercial success.

Martin Cooper
, a
Motorola

researcher and executive is considered
to be the inventor of the first practical mobile phone for
handheld

use in a non
-
vehicle setting, after a
long race against
Bell Labs

for the first portable mobile phone. Using a modern, if somewhat heavy portable
handset, Cooper made the first call on a handheld mobile phone on April 3, 1973 to his rival, Dr.
Joel S.
Engel

of
Bell Labs
.

The first commercially automated cellular network (the
1G
) was launched in Japan by
NTT

in 1979, initially in the metropolitan area of Tokyo. Within five years, the NTT n
etwork had been expanded
to cover the whole population of Japan and became the first nationwide 1G network. In 1981, this was
followed by the simultaneous launch of the
Nordic Mobile Telephone

(NMT) system in Denmark, Finland, Norway
and Sweden.

NMT was the first mobile phone network featuring international
roaming
. The first 1G network
launched in the USA was Chicago
-
based
Ameritech

in 1983 using the
Motorola DynaTAC

mobile phone. Several
countries then followed in the early
-
to
-
mid 1980s including the UK, Mexico and Canada.

The first "modern"
network technology on digital
2G

(second generation) cellular technology was launched by
Radiolinja

(now
part of
Elisa Group
) in 1991 in Fin
land on the
GSM

standard, which also marked the introduction of
competition in mobile telecoms when Radiolinja challenged incumbent
Telecom Finland

(now part of
TeliaSonera
) who ran a 1G NMT network.

In 2001, the launch of
3G

(Third Generation) was again in Japan by
NTT DoCoMo

on the
WCDMA

standard.

One of the newest 3G technologies to be implemented is
High
-
Speed Downl
ink
Packet Access

(HSDPA). It is an enhanced
3G

(third generation)
mobile telephony

communications protocol

in
the
high
-
speed packet access

(HSPA) family, also coined 3.5G,
3G+ or turbo 3G, which allows networks based
on
Universal Mobile Telecommunications System

(UMTS) to have higher data tr
ansfer speeds and capacity.

Before Cellular Phones
Mobile radio telephone

systems preceded modern cellular mobile telephony technology.
Since they were the predecessors of the first generation of cellular telephones, these systems are sometimes
retroactive
ly referred to as
pre cellular

(or sometimes zero generation) systems. Technologies used in pre
cellular systems included the
Push to Talk

(PTT or manual),
Mobile Telephone System

(MTS),
Improved Mobile
Telephone Service

(IMTS), and
Advanced Mobile Telephone System

(AMTS) systems. These early mobile telephone
systems can be distinguished from earlier closed
radiotelephone

systems in that they were available as a
commercial service that was part of the
public switched telephone network
, with their own telephone numbers,
rather than part of a closed network such as a police radio or taxi dispatch system.

These mobile telephones
were usually mounted in cars or trucks,
though briefcase models were also made. Typically, the transceiver
(transmitter
-
receiver) was mounted in the vehicle trunk and attached to the "head" (dial, display, and
handset) mounted near the driver seat.

They were sold through WCCs (Wireline Common Ca
rriers, AKA telephone
companies), RCCs (Radio Common Carriers), and two
-
way radio dealers.

Origins



Motorola

in conjunction with the
Bell System

operated the first commercial mobile telephone service
Mobile Telephone
System

(MTS) in the US in 1946, as a service of the wir
eline telephone company.



The
A
-
Netz

launched 1952 in
West Ge
rmany

as the country's first public commercial mobile phone network.



First automatic system was the Bell System's IMTS which became available in 1962, offering automatic dialing to and
from the mobile.



The Televerket opened its first manual mobile telepho
ne system in
Norway

in 1966. Norway was later the first country in
Europe

to get an automatic mobile telephone system.



The
Autoradiopuhelin

(ARP) launched in 1971 in
Finland

as the country's first public commercial mobile phone networ
k



The
B
-
Netz

launched 1972 in
West Germany

as the country's second public commercial mobile phone network (but the
f
irst one that did not require human operators to connect calls)

Radio Common Carrier
Parallel to
Improved Mobile Telephone Service

(IMTS)
in the US until the rollout of
cellular AMPS systems, a competing mobile telephone technology was called
Radio Common Carrier

or
RCC
. The
service was provided from the 1960s until the 1980s when cellular AMPS systems made RCC equipment obsolete.
These syst
ems operated in a regulated environment in competition with the Bell System's MTS and IMTS. RCCs
handled telephone calls and were operated by private companies and individuals. Some systems were designed
to allow customers of adjacent RCCs to use their fac
ilities but the universe of RCCs did not comply with any
single interoperable technical standard (a capability called
roaming

in modern systems). For example, the
phone of an Omaha, Nebraska

based RCC service would not be likely to work in Phoenix, Arizona
. At the end
of RCC's existence, industry associations were working on a technical standard that would potentially have
allowed roaming, and some mobile users had multiple decoders to enable operation with more than one of the
common signaling formats (600
/1500, 2805, and Reach). Manual operation was often a fallback for RCC roamers.

Roaming was not encouraged, in part, because there was no centralized industry billing database for RCCs.
Signaling formats were not standardized. For example, some systems use
d
two
-
tone sequential paging

to alert
a mobile or hand
-
held that a wired phone was trying to call them. Other systems used
DTMF
. Some used a
system called
Secode 2805

which transmitted an interrupted 2805 Hz tone (in a manner similar to IMTS
signaling) to alert mobiles of an offered call. Some radio equipment used with RCC systems was half
-
duplex,
push
-
to
-
talk equ
ipment such as Motorola hand
-
helds or RCA 700
-
series conventional two
-
way radios. Other
vehicular equipment had telephone handsets, rotary or pushbutton dials, and operated full duplex like a
conventional wired telephone. A few users had full
-
duplex briefc
ase telephones (radically advanced for their
day).

RCCs used paired UHF 454/459

MHz and VHF 152/158

MHz frequencies near those used by IMTS.

Rural Radiotelephone Service
Using the same channel frequencies as IMTS, the US
Federal Communications
Commission

authorized Rural Radiotelephone Service for fixed stations. Because RF channels were shared with
IMTS, the service was licensed only in are
as that were remote from large
Bureau of the Census

Met
ropolitan
Statistical Areas (MSAs)
.

Systems used UHF 454

MHz or 152

MHz radio channels to provide telephone service
to extremely rural places where it would be too costly to extend

cable plant. One such system was on a
454/459

MHz channel pair between the
Death Valley

tele
phone exchange

and
Stovepipe Wells, California
. This
specific system carried manual calls to the Traffic Service Position System (TSPS) center in Los

Angeles.
Stovepipe Wells callers went off
-
hook and were queried, "Number please," by a TSPS operator, who dialed the
call. Dial service was introduced to Stovepipe Wells in the mid
-
1980s. The radio link has since been
replaced by cable. The analog service

has since been replaced by
Basic Exchange Telephone Radio Service
, a
digital system using the same frequencies.

Features
All mo
bile phones have a number of features in common, but manufacturers also try to differentiate
their own products by implementing additional functions to make them more attractive to consumers. This has
led to great innovation in mobile phone development ove
r the past 20 years.

The common components found on
all phones are:



A battery, providing the power source for the phone functions



An input mechanism to allow the user to interact with the phone. The most common input mechanism is a
keypad
, but
touch screens

are also found in some high
-
end smartphones.



Basic
mobile phone services

to allow users to make calls and send text messages.



All
GSM

phones use a
SIM card

to allow an account to be swapped among devices. Some
CDMA

devices also have a
similar card called a
R
-
UIM
.



Individual GSM, WCDMA, iDEN and some satellite phone devices are uniquely identified by an
International Mobile
Equipment Identity

(IMEI) number.

Low
-
end mobile phones are often referred to as
feature phones
, and offer basic telephony, as well as
functions

such as playing music and taking photos, and sometimes simple applications based on generic
managed

platforms such as
Java ME

or BREW. Handsets with more advanced computing ability through the use of
native software applications became known as
smartphones
. The first smartphone was the
Nokia 9000
Communicator

in 1996 which added
PDA

functionality to the basic mobile phone at the time. As miniat
urization
and increased processing power of microchips has enabled ever more features to be added to phones, the
concept of the smartphone has evolved, and what was a high
-
end smartphone five years ago, is a standard
phone today.

Several phone series have
been introduced to address a given market segment, such as the RIM
BlackBerry

focusing on enterprise/corporate customer email needs; the SonyEricsson Walkman series of
musicphones and
Cybershot series of cameraphones; the
Nokia Nseries

of multimedia phones, the
Palm Pre

the
HTC Dream

and the Apple
iPhone
.

Other features that may be found on mobile phones include
GPS navigation
,
music (MP3) and video (
MP4
) playback,
RDS

radio receiver
, alarms, memo recording,
personal digital assistant

functions, ability to watch
streaming video
, video download,
video calling
,
built
-
in

cameras (1.0+
Mpx
) and
camcorders

(video recording), with
autofocus

and flash,
ringtones
, games,
PTT
,
memory card reader

(SD),
USB

(2.0), dual line support,
infrared
,
Bluetooth

(2.0) and
WiFi

connectivity,
instant messag
ing
, Internet e
-
mail and
browsing

and serving as a
wireless modem
.
Nokia

and the University of Cambridge demonstrated a
bendable

cell phone called the
Morph
.

Some phones can make
mobile payments

via direct mobile billing schemes
or through
contactless payments

if the phone and
point of sale

support
Near Field Communication

(NFC).

Some
of the largest mobile phone manufacturers and network providers along with many
retail merchants support, or
plan to support, contactless payments through NFC
-
equipped mobile phones.

Some phones have an
electromechanical
transducer

on the back which changes the electrical voice signal into mech
anical
vibrations. The vibrations flow through the cheek bones or forehead allowing the user to hear the
conversation. This is useful in the noisy situations or if the user is hard of hearing.

Software and applications
The most commonly used data application on mobile phones is
SMS

text messaging.
The first SMS text message was sent from a computer to a mobile phone in 1992 i
n the UK, while the first
person
-
to
-
person SMS from phone to phone was sent in Finland in 1993.

Other non
-
SMS data services used on
mobile phones include mobile music, downloadable logos and pictures, gaming, gambling, adult entertainment
and advertising.
The first downloadable mobile content was sold to a mobile phone in Finland in 1998, when
Radiolinja (now Elisa) introduced the downloadable ringtone service. In 1999, Japanese mobile operator NTT
DoCoMo introduced its mobile Internet service,
i
-
Mode
, which today is the world's largest mobile Internet
service.

The first mobile news service, delivered via SMS, was launched in Finland in 2000.
Mobile news

services are expanding with many organizations providing "on
-
demand" news services by SMS. Some also provide
"instant" news pushed out by SMS.

Mobile payments were first trialled in Finland in 1998 when two Coca
-
Cola
vendin
g machines in Espoo were enabled to work with SMS payments. Eventually, the idea spread and in 1999
the Philippines launched the first commercial mobile payments systems, on the mobile operators Globe and
Smart. Today, mobile payments ranging from
mobile banking

to mobile credit cards to mobile commerce are very
widely used in Asia and Africa, and in selected European markets.

Power Supply
Mobile phones generally obtain power fr
om
rechargeable

batteries. There are a variety of ways
used to charge cell phones, including
USB
, portable

batteries, mains power (using an
AC adapter
), cigarette
lighters (using an adapter), or a
dynamo
. In 2
009, the first wireless charger was released for consumer use.

Various initiatives, such as the EU
Common External Power Supply

have been announced to standardize the
interface to the charger, and to promote energy efficiency of mains
-
operated chargers. A star rating system
is promoted by some manufacturers, where

the most efficient chargers consume less than 0.03 watts and obtain
a five
-
star rating.

Battery
Formerly, the most common form of mobile phone batteries were
nickel

metal
-
hydride
, as they have a
low size and weight.
Lithium ion

batteries are sometimes used, as they are lighter and do not have the
voltage depression

that nickel metal
-
hydride batteries do. Many mobile phone manufacturers have now switched
to using
lithium

polymer batteries

as opposed to the older
Lithium
-
Ion
, the main advantages of this being
even lower weight and the possibility to make the

battery a shape other than strict cuboid.

Mobile phone
manufacturers have been experimenting with alternative power sources, including
solar cells
. A prototype
mini solar panel from Wysips was able use perfectly as 'live phone' with Android phone. The mini solar panel
can be installed on the Android phone screen, although the phone battery is still
needed due to the solar
panel solely has not been able to produce enough energy.

Sim card
GSM

mobile phones require a small

microchip

called a Subscriber Identity Module or
SIM Card
, to
function. The SIM card is approximate
ly the size of a small postage stamp and is usually placed underneath
the battery in the rear of the unit. The SIM securely stores the
service
-
subscriber key (IMSI)

used to
identify a subscriber on mobile telephony devices (such as mobile phones and computers). The SIM card allows
users to change phones by simply removing the SIM card from one mobile phone and inserting it into

another
mobile phone or broadband telephony device.

A SIM card contains its unique serial number, internationally
unique number of the mobile user (
IMSI
), security authentication and ciphering in
formation, temporary
information related to the local network, a list of the services the user has access to and two passwords
(PIN for usual use and PUK for unlocking).

SIM cards are available in three standard sizes. The first is the
size of a credit car
d (85.60

mm × 53.98

mm x 0.76

mm). The newer, most popular miniature version has the
same thickness but a length of 25

mm and a width of 15

mm, and has one of its corners truncated
(chamfered) to prevent misinsertion. The newest incarnation known as the 3F
F or micro
-
SIM has dimensions of
15

mm × 12

mm. Most cards of the two smaller sizes are supplied as a full
-
sized card with the smaller
card held in place by a few plastic links; it can easily be broken off to be used in a device that uses the
smaller SIM.

The first SIM card was made in 1991 by Munich smart card maker
Giesecke & Devrient

for the
Finnish wireless network operator
Radiolinja
. Giesecke & Devrient sold the first 300 SIM cards to Elisa (ex.
Radiolinja).

Those cell phones that do not use a SIM Card have the data programmed in to their memory. This
data is accessed by using a special digi
t sequence to access the "NAM" as in "Name" or number programming
menu. From there, information can be added, including a new number for the phone, new Service Provider
numbers, new emergency numbers, new Authentication Key or A
-
Key code, and a Preferred R
oaming List or PRL.
However, to prevent the phone being accidentally disabled or removed from the network, the Service Provider
typically locks this data with a Master Subsidiary Lock (MSL). The MSL also
locks

the device to a particular
carrier when it is sold as a
loss leader
.

The MSL applies only to the SIM, so once the contract has expired,
the MSL still applies to

the SIM. The phone, however, is also initially locked by the manufacturer into the
Service Provider's MSL. This lock may be disabled so that the phone can use other Service Providers' SIM
cards. Most phones purchased outside the U.S. are unlocked phones b
ecause there are numerous Service
Providers that are close to one another or have overlapping coverage. The cost to unlock a phone varies but
is usually very cheap and is sometimes provided by independent phone vendors.

A similar module called a
Removable User Identity Module

or RUIM card is present in some CDMA networks, notably in China and
Indonesia.

Multi
-

card hybrid phones
A hybrid mobile ph
one can take more than one SIM card, even of different types.
The SIM and RUIM cards can be mixed together, and some phones also support three or four SIMs

From 2010 onwards they became popular in India and Indonesia and other emerging markets,

attributed to the
desire to obtain the low
est on
-
net calling rate.

Display
Virtually all mobile phones have an integrated
display device
, some with touchscreen function. The
main measurements for
screen size

varies greatly by model.

Manufacturers use different methods to specify
display size, usually width and height in pixels or the diagonal measured in inches.

I
n 2011, a 3G
Android

Smartphone

was launched with dual 3.5

inch screens. Fur
thermore, the screens can be combined into a single
4.7

inch which turns it into a
Tablet computer
. It uses a single
Snapdragon

processor.

Central processing unit
Mobile phones have
cent
ral processing units

(CPUs), similar to those in computers,
but optimised to operate in low power environments.

Mobile CPU performance depends not only on the clock
rate (generally given in multiples of
hertz
)

but also the
memory hierarchy

also greatly affects overall
performance. Because

of these problems, the performance of mobile phone CPUs is often more appropriately
given by scores derived from various standardized tests to measure the real effective performance in
commonly used applications.

Mobile phones in society
The world's large
st individual mobile operator by subscribers is
China Mobile

with
over 500 million mobile phone subscribers.

Over 50 mobile operators have over 10 million subscribers each,
and over 150 mobile operators have at least one million subscribers by the end of 2009 (source wireless
intelligence). In February 2010, there were 4.6 billion mobile phone subscribers, a
number that is estimated
to grow.

Competitive forces emerged in the Asia Pacific (excluding Japan) region at Q3 2010 to the detriment
of market leader Nokia. Brands such as Micromax
,
Nexian
, and i
-
Mobile chipped away at Nokia's market share
plus Android powered smartphones also gained momentum across the region at the cost of Nokia.

Based on IDC
India, Nokia's market sha
re dropped significantly to 36 percent in the second quarter, from 56.8 percent in
the same quarter last year and further drop to 31.5 percent in the th ird quarter, reflecting the growing
share of Chinese and Indian vendors of low
-
end mobile phones.

Based on IDC in the last quarter of 2010, RIM
has been knocked out from the top five list global mobile phone sellers. The number one rank is still Nokia
followed by Samsung, LG Electron
ics, ZTE and Apple. For the first time Chinese ZTE is among the top five
list and mainly make of lower cost phones.

For the year of 2010, Sony Ericsson and Motorola are out from the

top of five list and have been replaced by LG Electronics and Apple. Significant increase from 16.5 percent
to 30.6 percent has been done by many small not yet recognized brands (some of them are new brands)


Others
-
2. Total sales in 2010 to end users we
re 1.6 billion units or increase by 31.8 percent from the year
of 2009.

In Q1 2011, Apple surpassed Nokia as the world's top handset vendor in revenue and Nokia market
share drop co
ntinuously to 29 percent in Q1 2011 as the lowest level since the late 1990s. In June 2011,
Nokia has also announced that in Q2 2011 the sales and margins are expected to be much lower than
anticipated due to global competition in both low
-
and
-
high end mar
kets.

At April 6, 2011 market
capitalization of HTC surpassed Nokia with $33.8 billion over $33.4 billion respectively. The credit agency
was also downgraded Nokia's debt from A2 to

A3.

Market share of world's top 5 mobile vendor

Source

Date

Nokia

SAMSUNG

LG

Apple

ZTE

Others

References

Gartner

Q2/2011

22.8%

16.3%

5.7%

4.6%

3.0%

35.8%


IDC

Q2/2011

24.2%

19.2%

6.8%

5.6%

4.5%

39.7%




Source: Gartner & IDC, Q2
-
2011



Note: Vendor shipments are bran
ded shipments and exclude OEM sales for all vendors

By year
-
over
-
year at Q2, worldwide sales of mobile devices grew 16.5 percent, to reach 428.7 million units.
Others still rose and achieved almost a half of market share.

June 2011: In 3 years, RIM has los
sed about 82
percent of the capitalization. As a barometer in North America RIM's market share dropped significantly from
54 percent to 13 percent in the last 2 years.

Other manufac
turers outside of Top Five include (June 2011
data)
Research In Motion Ltd.

(RIM),
HTC
Corporation
,
Motorola
,
Huawei
,
Sony Ericsson
,

while the following
has very small market share each
Audiovox

(now
UTStarcom
),
BenQ
-
Siemens
,
CECT
,
Fujitsu
,
Kyocera
,
Mitsubishi
Electric
,
NEC
,
Panasonic
,
Palm
,
Pantech Wireless Inc.
,
Philips
,
Qualcomm Inc.
,
Sagem
,
Sanyo
,
Sharp
,
Sierra
Wireless
,
Just5
,
SK Teletech
,
T&A Alcatel
,
Trium
,
Toshiba
,
Vidalco

and so many
China
's,
India
's and
Indonesia
's brands. There are

also specialist communication systems related to (but distinct from) mobile
phones.

Media
In 1998, one of the first examples of selling media content through the mobile phone was the sale of
ringtones

by Radiolinja in Finland. Soon afterwards, other media content appeared such as news, videogames,
jokes, horoscopes, TV content and advertising. Most early content for mobile tended to be copies of legacy
media, such as the banner advertiseme
nt or the TV news highlight video clip. Recently, unique content for
mobile has been emerging, from the ringing tones and ringback tones in music to "mobisodes," video content
that has been produced exclusively for mobile phones.

In 2006, the total value o
f mobile
-
phone
-
paid media
content exceeded Internet
-
paid media content and was worth 31 billion dollars (source Informa 2007). The
value of music on phones was worth 9.3 billion dollars in 2007 and gaming was worth over 5 billion dollars
in 2007.

The advent of media on the mobile phone has also produced the opportunity to identify and track
Alpha Users

or Hubs, the most influential members of any social community. AMF Ventures measured in 2007 the
relative accuracy of three mass media, and found that audience measures on mobile were nine times more
accurate th
an on the Internet and 90 times more accurate than on TV.

The mobile phone is often called the
Fourth Screen (if counting cinema, TV and PC screens as the first three) or Third Screen (counting only TV
and PC screens).
[
weasel

words
]

It is also called the
Seventh of the Mass Media

(with Print, Recordings, Cinema,
Radio,

TV and Internet the first six).

Privacy
The movements of a mobile phone user can be tracked by their service provider and, if desired, by
law enforcement agencies and their government. Both the
SIM card

and the handset can be tracked.

China has
proposed using this technology to track commuting patterns of Beijing city residents.

Usage
Mobile phones are used for a variety of purposes, including keeping in touch with family members,
conducting business, and having access to a telephone in the event of an emergency. Some people carry more
than on
e cell phone for different purposes, such as for business and personal use. Multiple SIM cards may
also be used to take advantage of the benefits of different calling plans

a particular plan might provide
cheaper local calls, long
-
distance calls, internati
onal calls, or roaming. A study by
Motorola

found that
one in ten cell phone subscribers have a second phone that often is kept secret from other family members.
These phones may be used t
o engage in activities including extramarital affairs or clandestine business
dealings.

The mobile phone has also been used in a variety of diverse contexts in society, for example:



Organizations that aid victims of domestic violence may offer a cell phone to potential victims without the abuser's
knowledge. These devices are often old phones that are donated and refurbished to meet the victim's emergency needs.



The advent of widespread text messaging has resulted in the
cell phone novel
; the first literary genre to emerge from
the
cellular age via
text messaging

to a website that collects the novels as a whole.

Paul Levinson,
in Information on the Move
(2004), says "...nowadays, a writer can write just about as easily, anywhere, as a reader can read" and they are "not only
personal but portable."



Mobile telephony

also facilitates activism and public journalism being explored by
Reuters

and
Yahoo!

and small
independent news companies such as
Jasmine News

in Sri Lan
ka.



Mobile phones help lift poor out of poverty. The United Nations has reported that mobile phones

spreading faster than
any other information technology

can improve the livelihood of the poorest people in developing countries. The
economic benefits of mo
bile phones go well beyond access to information where a
landline

or Internet is not yet available
in rural areas, mostly in
Least Developed Countries
. Mobile phones have spawned a wealth of micro
-
enterprises, offering
work to people with little education and few resources, such as selling airtime on the streets and repairing or refurbishing
ha
ndsets.



In Mali and some African countries, villagers sometimes had to go from village to village all day, covering up to 20
villages, to let friends and relatives know about a wedd
ing, a birth or a death, but such travel is no longer necessary if the
villages are within the coverage area of a mobile phone network. Like in many African countries, the coverage is better
than that of landline networks, and most people own a mobile phon
e. However, small villages have no electricity, leaving
mobile phone owners to have to recharge their phone batteries using a
solar panel

or motorcycle battery.



The TV industry has recently started using mobile phones to drive live TV viewing through mobile apps, advertising,
social tv
, and
mobile TV
.

86% of Americans use their mobile phone while watching TV.



In March 2011, a pilot project experimenti
ng with
branchless banking

was launched by the
Inte
rnational Finance
Corporation
, a member of the
World Bank
, and Bank Harapan Bali, a subsidiary of
Bank Mandi
ri

the biggest bank in
Indonesia and one of the cellular operators in
Bali
. Its aim is to increase the amount of bank customers. In Indonesia, only
60 million people have a bank account even thou
gh banks have existed for more than a hundred years, whereas 114 million
people have become users of mobile phones in only two decades. Branchless banking has been successful in Kenya, South
Africa and Philippines.

Sharing
In some parts of the world, mobile phone sharing is common. It is prevalent in urban India, as
families and groups of friends often share one or more mobiles among their members. There are obvious
economic benefits
, but often familial customs and traditional gender roles play a part.

For example, in
Burkina Faso, it is not uncommon for a village to have access to only one mobile phone. The ph
one is
typically owned by a person who is not natively from the village, such as a teacher or missionary, but it is
expected that other members of the village are allowed to use the cell phone to make necessary calls.

Restrictions While Driving
Mobile phone use while driving is common but controversial. Being distracted
while operating a motor vehicle has been shown to increase the risk of accident. Because of this, many
jurisdiction
s prohibit the use of mobile phones while driving. Egypt, Israel, Japan, Portugal and Singapore
ban both handheld and hands
-
free use of a mobile phone; others

including the UK, France, and many U.S.
states

ban handheld phone use only, allowing hands
-
free
use.

Due to the increasing complexity of mobile
phones, they are often more like mobile computers in their available uses. This has introduced additional
difficulties for law enforcement officials in distinguishing one usage from another as drivers use the
ir
devices. This is more apparent in those countries which ban both handheld and hands
-
free usage, rather those
who have banned handheld use only, as officials cannot easily tell which function of the mobile phone is
being used simply by looking at the dri
ver. This can lead to drivers being stopped for using their device
illegally on a phone call when, in fact, they were using the device for a legal purpose such as the phone's
incorporated controls for car stereo or
satnav
.

A recently published study has reviewed the incidence of
mobile phone use while cycling and its effects on behaviour and safety.

In schools
Some schoo
ls limit or restrict the use of mobile phones. Schools set restrictions on the use of
mobile phones because of the use of cell phones for cheating on tests, harassment and bullying, causing
threats to the schools security, distractions to the students, and

facilitating gossip and other social
activity in school. Many mobile phones are banned in school locker room facilities, public restrooms and
swimming pools due to the built
-
in cameras that most phones now feature.

Privacy
Governments, law enforcement and

intelligence services use mobiles to perform surveillance in the UK
and the US They possess technology to activate the microphones in cell phones remotely in order to listen to
conversations that take place near to the person who holds the phone.

Mobile phones are also commonly used
to collect location data. While the phone is turned

on, the geographical location of a mobile phone can be
determined easily (whether it is being used or not), using a technique known
multilateration

to calculate
the differen
ces in time for a signal to travel from the cell phone to each of several
cell towers

near the
owner of the phone.

Health Effects
On 31st May 2011, the
World Health Organization

confirmed that mobile phone use may
represent a long
-
term health risk
, classifying mobile phone radiation as a "carcinogenic hazard" and
"possibly carcinogenic to humans" after a team of scientists reviewed peer
-
review studies on cell phone
safety.

One study of past cell phone use cited in the report showed a "40% increased risk for
gliomas

(brain
cancer) in the highest category of heavy users (repo
rted average: 30 minutes per da
y over a 10‐year
period)."

This is a reversal from their prior position that cancer was unlikely to be caused by cellular
phones or their base stations and that reviews had found no

convincing evidence for other health effects.

Certain countries, including Fran
ce, have warned against the use of cell phones especially by minors due to
health risk uncertainties.

The effect mobile phone radiation has on human health is the subject of recent
interest and study, as a result of the enormous increase in mobile phone usage throughout the world (as of
June 2009
, there were more than 4.3 billion users worldwid
e
). Mobile phones use
electromagnetic radiat
ion

in
the
microwave

range, which some believe may be harmful to human health. A large body of research exists,
both
epidemiological

and experimental, in
non
-
human animals

and in humans, of which the majority shows no
definite causative relationship between exposure to mobile phones and h
armful biological effects in humans.
This is often paraphrased simply as the balance of evidence showing no harm to humans from mobile phones,
although a significant number of individual studies do suggest such a relationship, or are inconclusive.
Other
digital wireless systems
, such as data communication networks, produce similar radiation.

At least
some recent studies have found
an association between cell phone use and certain kinds of brain and salivary
gland tumors. Lennart Hardell and other authors of a 2009 meta
-
analysis of 11 studies from peer
-
reviewed
journals concluded that cell phone usage for at least ten years “approxim
ately doubles the risk of being
diagnosed with a brain tumor on the same ('ipsilateral') side of the head as that preferred for cell phone
use.”

In addition, a mobile phone can spre
ad
infectious diseases

by its frequent contact with hands. One
study came to the result that
pathogenic bacteria

are present on approximately 40% of mobile phones
belonging to patients in a hospital, and on approximately 20% of mobile phones belonging to hospital staff.

There have been concerns that cell phone radiation may be negatively affecting
honeybees
,

but the results
have been disputed.

Future Evolution: Broadband 4
th

Generation (3G&4G)
The recently released 4th generation, also known as
Beyond 3G
, aims to provide
broadband wireless access

with nominal data rates of 100

Mbit/s to fast moving
devices, and 1 Gbit/s to stationary devices defined by the
ITU
-
R

4G systems may be based on the
3GPP

LTE
(
Long Term Evolution
)

cellular standard, offering peak bit rates of 326.4 Mbit/s. It may perhaps also be
based on
WiMax

or
Flash
-
OFDM

wireless
metropolitan area network technologies that promise
broadband wireless
access

with speeds that reaches 233 Mbit/s for mobile users. The radio interface in

these systems is based
on all
-
IP
packet switching
,
MIMO

diversity,
multi
-
carrier modulation

schemes,
Dynami
c Channel Assignment

(DCA) and
channel
-
dependent scheduling
. A 4G system should be a complete replacement for current network
infrastructure and is

expected to be able to provide a comprehensive and secure IP solution where voice,
data, and streamed multimedia can be given to users on a "Anytime, Anywhere" basis, and at much higher data
rates than previous generations.
Sprint

in the US has claimed its WiMax network to be "4G network" which
most cellular telecoms standardization experts dispute repeatedly around the world. Sprint's 4G is seen as a
marketing gimmick as WiMax i
tself is part of the 3G air interface. The officially accepted, ITU ratified
standards
-
based 4G networks are not expected to be commercially launched until 2011. In March 2011,
KT

from
South Korea announced that they has expanded its high
-
speed wireless broadband network by
4G

W
iBro

cover 85
percent of the population. It is the largest broadband network covered in the world, followed by Japan and
US with 70 percent and 36 percent respectively.

At the begi
nning of 2011, some major mobile phone companies
have released their 4G mobile phones such as from Motorola, HTC and Samsung.